High-temperature tolerance of flowers

Abstract

Similar to the other crops, production of floricultural plants (crops for ornamental purposes) is susceptible to high temperature. High temperature changes flowering time, causing problems in the schedule of shipment to the market.Consistent with the idea of plant adaptation to climate, induction of long-day spring flowers (Arabidopsis/thale cress) is accelerated by high temperature, whereas induction of short-day autumn flowers (chrysanthemum) is delayed by high temperature. High temperature also reduces flower size and causes paler petal colors (e.g. chrysanthemum, rose, and Eustoma) and fruit skin colors (e.g. grape and apple), thus decreasing the quality of flowers and fruits. The reasons for high-temperature caused disorders are not necessarily clear, but high temperature influences part of gene expressions involved in flowering time (FT, Flowering Locus T) and pigment synthesis (such as CHS, chalcone synthase). High-temperature- tolerant cultivars are identified or selected in floricultural and pomological (fruit) crops. High-temperature effects could be alternatively attenuated by shading or supplementation of magnesium. Heat is sometimes required for flowers: some plant species generate heat in flowers by themselves. Petal color affects flower temperature. Relationships between flower and heat in these various aspects are illustrated by photographs and illustrations of the representative studies in this research field.